SPECIFIC AIM: 1. Determine the production of proinflammatory cytokines, H202 and prostaglandin E2 in the mucosa of patients with BE. 2. Analyze the effect of PPI treatment on the production of cytokines, PGE2 and H202 and the progression from metaplasia to dysplasia. 3. Determine the effects of acid exposure on cytokines, PGE2 and H202 production in esophogeal mucosa of BE patients. 4. Determine signaling pathways involved in the upregulation of COX-2 following acid exposure. 5. Determine whether IL-lb induces production of IL-6.